Rob Moore

'Captain America' a box-office trouper

'Captain America' a box-office trouper

"Captain America: The First Avenger" outmuscled its competition at the box office this weekend, including Harry Potter, and had the most forceful opening of any big-budget superhero movie released this summer.

The 3-D film, which stars Chris Evans as a puny military reject transformed into a superhero via a secret government program, grossed a solid $65.8 million in the U.S. and Canada, according to an estimate from distributor Paramount Pictures. That was over $10 million more than both "X-Men: First Class" and "Green Lantern" collected upon their debuts in June and just a tad above the $65.7-million opening weekend for "Thor" in...